| Message ID | 20201112103506.5875-1-xie.he.0141@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net,v2] net: x25: Increase refcnt of "struct x25_neigh" in x25_rx_call_request | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for net |
| netdev/subject_prefix | success | Link |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 7 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/header_inline | success | Link |
| netdev/stable | success | Stable not CCed |
On Thu, 12 Nov 2020 02:35:06 -0800 Xie He wrote: > The x25_disconnect function in x25_subr.c would decrease the refcount of > "x25->neighbour" (struct x25_neigh) and reset this pointer to NULL. > > However, the x25_rx_call_request function in af_x25.c, which is called > when we receive a connection request, does not increase the refcount when > it assigns the pointer. > > Fix this issue by increasing the refcount of "struct x25_neigh" in > x25_rx_call_request. > > This patch fixes frequent kernel crashes when using AF_X25 sockets. > > Fixes: 4becb7ee5b3d ("net/x25: Fix x25_neigh refcnt leak when x25 disconnect") > Cc: Martin Schiller <ms@dev.tdt.de> > Signed-off-by: Xie He <xie.he.0141@gmail.com> Applied, thanks!
diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c index 046d3fee66a9..a10487e7574c 100644 --- a/net/x25/af_x25.c +++ b/net/x25/af_x25.c @@ -1050,6 +1050,7 @@ int x25_rx_call_request(struct sk_buff *skb, struct x25_neigh *nb, makex25->lci = lci; makex25->dest_addr = dest_addr; makex25->source_addr = source_addr; + x25_neigh_hold(nb); makex25->neighbour = nb; makex25->facilities = facilities; makex25->dte_facilities= dte_facilities;
The x25_disconnect function in x25_subr.c would decrease the refcount of "x25->neighbour" (struct x25_neigh) and reset this pointer to NULL. However, the x25_rx_call_request function in af_x25.c, which is called when we receive a connection request, does not increase the refcount when it assigns the pointer. Fix this issue by increasing the refcount of "struct x25_neigh" in x25_rx_call_request. This patch fixes frequent kernel crashes when using AF_X25 sockets. Fixes: 4becb7ee5b3d ("net/x25: Fix x25_neigh refcnt leak when x25 disconnect") Cc: Martin Schiller <ms@dev.tdt.de> Signed-off-by: Xie He <xie.he.0141@gmail.com> --- net/x25/af_x25.c | 1 + 1 file changed, 1 insertion(+)